Question

tolong bantu jawabb dongg​

Answer 1

Verified answer

Penjelasan dengan langkah-langkah:

deret = 4 + 2 + 1 + 1/2 + ..

rumus un = a x r^n - 1

a = 4

a. mencari rasio

un = a x r^n - 1

u2 = 4 x r^2 - 1

2 = 4r

r = 1/2

b. suku ke 12

un = ar^n - 1

u12 = 4 x (1/2)^12 - 1

u12 = 4 x 1/2^11

u12 = 1/512

c. jumlah 12 suku pertama

sn = a(1 - r^n)/(1 - r)

s12 = 4(1 - (1/2)^12)/(1 - 1/2)

s12 = 8 - 1/2^9

s12 = 4.095/512